Electricity became a subject of scientific interest in the late 17th century. Over the next two centuries a number of important discoveries were made including the
incandescent light bulb and the
voltaic pile. Probably the greatest discovery with respect to power engineering came from
Michael Faraday who in 1831 discovered that a change in magnetic flux induces an
electromotive force in a loop of wire—a principle known as
electromagnetic induction that helps explain how generators and transformers work. In 1881 two electricians built the world's first power station at
Godalming in England. The station employed two waterwheels to produce an alternating current that was used to supply seven Siemens
arc lamps at 250 volts and thirty-four
incandescent lamps at 40 volts. However supply was intermittent and in 1882
Thomas Edison and his company, The Edison Electric Light Company, developed the first steam-powered electric power station on Pearl Street in New York City. The
Pearl Street Station consisted of several generators and initially powered around 3,000 lamps for 59 customers. The power station used
direct current and operated at a single voltage. Since the direct current power could not be easily transformed to the higher voltages necessary to minimise power loss during transmission, the possible distance between the generators and load was limited to around half-a-mile (800 m). That same year in London
Lucien Gaulard and
John Dixon Gibbs demonstrated the first transformer suitable for use in a real power system. The practical value of Gaulard and Gibbs' transformer was demonstrated in 1884 at
Turin where the transformer was used to light up of railway from a single
alternating current generator. Despite the success of the system, the pair made some fundamental mistakes. Perhaps the most serious was connecting the primaries of the transformers in
series so that switching one lamp on or off would affect other lamps further down the line. Following the demonstration
George Westinghouse, an American entrepreneur, imported a number of the transformers along with a
Siemens generator and set his engineers to experimenting with them in the hopes of improving them for use in a commercial power system. One of Westinghouse's engineers,
William Stanley, recognised the problem with connecting transformers in series as opposed to
parallel and also realised that making the iron core of a transformer a fully enclosed loop would improve the
voltage regulation of the secondary winding. Using this knowledge he built the world's first practical transformer based alternating current power system at
Great Barrington, Massachusetts in 1886. In 1885 the Italian physicist and electrical engineer
Galileo Ferraris demonstrated an
induction motor and in 1887 and 1888 the Serbian-American engineer
Nikola Tesla filed a range of patents related to power systems including one for a practical two-phase induction motor which Westinghouse licensed for his AC system. By 1890 the power industry had flourished and power companies had built thousands of power systems (both direct and alternating current) in the United States and Europe – these networks were effectively dedicated to providing electric lighting. During this time a fierce rivalry in the US known as the "
war of the currents" emerged between Edison and Westinghouse over which form of transmission (direct or alternating current) was superior. In 1891, Westinghouse installed the first major power system that was designed to drive an electric motor and not just provide electric lighting. The installation powered a synchronous motor at
Telluride, Colorado with the motor being started by a Tesla induction motor. On the other side of the Atlantic,
Oskar von Miller built a 20 kV 176 km three-phase transmission line from
Lauffen am Neckar to
Frankfurt am Main for the Electrical Engineering Exhibition in Frankfurt. In 1895, after a protracted decision-making process, the
Adams No. 1 generating station at
Niagara Falls began transmitting three-phase alternating current power to Buffalo at 11 kV. Following completion of the Niagara Falls project, new power systems increasingly chose
alternating current as opposed to
direct current for electrical transmission. ==Twentieth century==